Negatively charged ion-exchange membranes have been proposed for the separation and/or purification of biomolecules such as proteins, amino acids, and nucleic acids. For the ion exchange membrane to perform effectively in the above applications, the membrane should satisfy several important parameters. For example, the membrane should exhibit high rates of fluid flow. The membrane should have high dynamic binding capacity for biomolecules, and should be capable of selectively binding the biomolecules, which have different surface charges. The membrane should, therefore, have low non-specific binding, e.g., resulting from hydrophobic interactions. The membrane should withstand high treatment fluid velocities. The preparation of the membrane should not involve chemistries and processes that are cumbersome to practice. Some of the cation exchange membranes known heretofore suffer from the failure to satisfy one or more of the parameters set forth above.
Accordingly, there exists a need for a cation exchange membrane that exhibits high rates of fluid flow. There further exists a need for a cation exchange membrane that has high dynamic binding capacity and selectivity for biomolecules. There further exists a need for a membrane that has low non-specific binding or low binding that results from hydrophobic interactions. There further exists a need for a membrane that can withstand high fluid flow velocities. There further exists a need for a membrane that involves preparation chemistries and/or processes that are not cumbersome to practice.
These advantages of the present invention, as well as additional inventive features, will be apparent from the description of the invention provided herein.